NPR : Q&A: What's Behind High Gas Prices?

"If a gallon of gasoline costs $2.90 (this week's average, according to the Energy Department), crude oil accounts for about $1.60. The cost of crude oil on the futures market has risen about 33 percent in the last year....Refining costs add another 64 cents or so to a gallon of gasoline. Refining margins have increased from a few years ago, and are especially high this spring, because many refineries are currently shut down for seasonal maintenance."

and later:

"Big oil companies are making most of their money by producing crude oil. They invested in oil fields when prices were much lower, with the expectation that they could break even at, say, $25 per barrel. Since the market price is now more than $70 a barrel, the extra money is gravy....they can no more control those prices than a farmer can dictate what he gets for a bushel of corn...f oil companies could control the price of crude oil, they would not have allowed the price to fall to $10 a barrel as it did in 1998."